Roof drills are used for drilling holes in rock in the roof of mines for installing roof bolts. The drills are typically in the form of a drive body having a bit at the forward end with a hard wearresistant material, such as tungsten carbide rigidly secured to the bit.
U.S. Pat. No. 4,190,128 to Emmerich relates to a roof drill having openings in the bit which connect to a hole in the drive body for the passage of air and removal of detritus.
U.S. Pat. No. 3,032,129 to Fletcher et al relates to a drill bit wherein the air is drawn into the drive body through open portions on each side of the bit.
U.S. Pat. No. 3,434,552 to Bower, Jr. relates to a bit having a slot with a cutting insert loosely held within the slot for free endwise sliding movement relative to the slot.
U.S. Pat. No. 3,434,553 to Weller relates to a drill where the center insert socket is formed by notching the opposite sides of the tube at the end 13 and bending the tube end wall to form two straight side support walls 14 and an outwardly bowed portion 15 which forms a duct closed on one side by the outer inset. The insert may be held between the walls by brazing or by a pin 16.
U.S. Pat. No. 3,415,332 to Bower, Jr. relates to a drill bit where the tubular holder has a pair of transversely aligned slots within which a pair of flat narrow, elongated plates are mounted. A cutter bit is positioned between the plates and the entire assembly is held together by a pin passing through the tubular holder, the plates, and the bit.